Organ-Specific Targeted Phenolic Profiling, Antioxidant, and Enzyme-Inhibitory Activities of the Gypsophilous Endemic Hedysarum pestalozzae.

The present study provides an integrative, targeted phenolic-bioactivity mapping of Hedysarum pestalozzae Boiss., an endemic Fabaceae species from gypsum habitats of Türkiye. Methanolic extracts of flowers, leaves, stems, and roots were comparatively evaluated for their phenolic profiles, antioxidant potentials, and enzyme inhibitory effects. Targeted LC-ESI-MS/MS analysis of selected phenolics revealed organ-dependent chemical profiles, with flowers exhibiting the highest accumulation of flavonols-hyperoside, kaempferol, quercetin-and phenolic acids such as protocatechuic acid, together with the flavanone glycoside hesperidin, while stems and roots were enriched in catechin, verbascoside, vanillin, and eriodictyol. The antioxidant capacities, assessed through multiple assays (CUPRAC, FRAP, DPPH, ABTS, metal chelation), were integrated using the Relative Antioxidant Capacity Index (RACI), ranking flowers as the most active organ, followed by roots, leaves, and stems. Correlation analysis demonstrated strong positive associations between phenolic abundance and electron-transfer assays, whereas metal chelation showed inverse trends, suggesting distinct antioxidant mechanisms. All extracts exhibited moderate inhibition against cholinesterases, tyrosinase, α-amylase, and α-glucosidase, implying multifunctional enzyme-modulating potential. The root extract showed the highest cholinesterase inhibition, and leaf extract was most effective against α-amylase. These findings indicate that H. pestalozzae exhibits organ-dependent chemical diversity and a broad range of biological activities. The present study provides preliminary evidence that H. pestalozzae may represent a promising source of bioactive compounds for future phytochemical and biological investigations, warranting further bioassay-guided fractionation, compound isolation, cellular studies, and in vivo validation.